Ablation, as it pertains to the present specification, relates to the removal or destruction of a body tissue, via the introduction of a destructive agent, such as radiofrequency energy, laser energy, ultrasonic energy, cyroagents, or steam. Ablation is commonly used to eliminate diseased or unwanted tissues, such as, but not limited to cysts, polyps, tumors, hemorrhoids, and other similar lesions.
Steam-based ablation systems, such as the ones disclosed in U.S. Pat. Nos. 9,615,875, 9,433,457, 9,376,497, 9,561,068, 9,561,067, and 9,561,066, disclose ablation systems that controllably deliver steam through one or more lumens toward a tissue target. One problem that all such steam-based ablation systems have is the potential overheating or burning of healthy tissue. Steam passing through a channel within a body cavity heats up surfaces of the channel and may cause exterior surfaces of the medical tool, other than the operational tool end itself, to become excessively hot. As a result, physicians may unintentionally burn healthy tissue when external portions of the device, other than the distal operational end of the tool, accidentally contacts healthy tissue. U.S. Pat. Nos. 9,561,068, 9,561,067, and 9,561,066 are hereby incorporated herein by reference.
Furthermore, it is often desirable to rapidly cool a treatment area after the application of steam or some other ablative agent. Current systems largely rely, however, on a natural cooling process that prolongs treatment time. Alternatively, current medical treatment methods may flush an area with fluid, but that requires implementing a separate medical tool, thereby complicating the procedure and also prolonging treatment times.
It is therefore desirable to have steam-based ablation devices that integrate into the device itself safety mechanisms which prevent unwanted burning during use. It is further desirable to be able to provide a way to augment the natural cooling process to thereby decrease treatment time. Finally, it is desirable to provide an easy to implement cooling mechanism that does not rely on a separate medical tool to deliver fluid to cool the treatment area.